/**
 * The ReadOnlyManager manages the database and rendering releated to read only pads
 */

/*
 * 2011 Peter 'Pita' Martischka (Primary Technology Ltd)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS-IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


var db = require("./DB");
var randomString = require("../utils/randomstring");

/**
 * returns a read only id for a pad
 * @param {String} padId the id of the pad
 */
exports.getReadOnlyId = async function (padId)
{
  // check if there is a pad2readonly entry
  let readOnlyId = await db.get("pad2readonly:" + padId);

  // there is no readOnly Entry in the database, let's create one
  if (readOnlyId == null) {
    readOnlyId = "r." + randomString(16);
    db.set("pad2readonly:" + padId, readOnlyId);
    db.set("readonly2pad:" + readOnlyId, padId);
  }

  return readOnlyId;
}

/**
 * returns the padId for a read only id
 * @param {String} readOnlyId read only id
 */
exports.getPadId = function(readOnlyId)
{
  return db.get("readonly2pad:" + readOnlyId);
}

/**
 * returns the padId and readonlyPadId in an object for any id
 * @param {String} padIdOrReadonlyPadId read only id or real pad id
 */
exports.getIds = async function(id) {
  let readonly = (id.indexOf("r.") === 0);

  // Might be null, if this is an unknown read-only id
  let readOnlyPadId = readonly ? id : await exports.getReadOnlyId(id);
  let padId = readonly ? await exports.getPadId(id) : id;

  return { readOnlyPadId, padId, readonly };
}
